Valve

ABSTRACT

A valve has a housing provided with an inlet for pressurized fluid, a valve seat having a seating surface, and a valve member exposed to the incoming pressurized fluid and having a cooperating surface juxtaposed and normally in engagement with the seating surface. At least one of these surfaces is provided with a shallow recess in which a conduit terminates which communicates with the inlet so as to admit into the recess sufficient pressurized fluid to lift the valve member off the valve seat. A control valve is interposed in the conduit and can be operated to permit the flow of pressurized fluid therethrough and into the recess.

waited States Patent [1 1 Kayser 1 Oct. 30, 1973 VALVE [76] Inventor:Lutz Tilo Kayser, D-7 Stuttgart, Pnmary Emmmer Amld RosemhalAttorneyMichael S. Striker [57] ABSTRACT A valve has a housing providedwith an inlet for pressurized fluid, a valve seat having a seatingsurface, and a valve member exposed to the incoming pressurized fluidand having a cooperating surface juxtaposed and normally in engagementwith the seating surface. At least one of these surfaces is providedwith a shallow recess in which a conduit terminates which communicateswith the inlet so as to admit into the recess sufficient pressurizedfluid to lift the valve member off the valve seat. A control valve isinterposed in the conduit and can be operated to permit the flow ofpressurized fluid therethrough and into the recess.

8 Claims, 2 Drawing Figures Patented Oct. 30, 1973 3,768,770

Figla Fig.1b

VALVE The present invention relates to a valve, and more particularly toa valve which controls the flow of pressurized fluid. Still moreparticularly the invention relates to a valve in which a main valvemember controlling the flow of pressurized fluid is moved to openposition when a branch flow of the incoming pressurized fluid isadmitted by an auxiliary valve member to the main valve member so as tolift the latter off its valve seat.

Constructions of the general type here concerned are already known fromthe prior art. For instance, one prior-art valve construction has avalve member which is pressed against its valve seat by the pressurizedfluid whose flow it controls, and which can be lifted off its valve seatby diverting via an auxiliary valve some of the pressurized fluidagainst the main valve member. The main valve member itself has a hollowpiston portion which, when the valve is closed, is filled withpressurized fluid and which fluid is permitted to escape from the pistonportion upon opening of the auxiliary valve. in this prior artconstruction it has been observed that the main valve member with thehollow valve piston can be raised off its valve seat only rather slowly,because the outlet bore in the hollow valve piston is quite small andthe pressurized fluid in the valve piston can be displaced through theoutlet bore -when the auxiliary valve controlling the latter is openedonly slowly. Evidently, the response time of a valve is important in agreat many applications and the slow lifting-off of the main valvemember in the prior-art construction is found to be a disadvantage insuch instances.

A further prior-art proposal concerns a valve construction in which,when the valve is operated, a portion of the valve piston surface isinitially subjected to fluid pressure, and therafter the total surfaceof the valve piston is subjected to this fluid pressure. This also, hasnot been found to be entirely satisfactory for various reasons, acomment which applies to still another prior-art proposal in which anelectromagnetic arrangement is utilized.

Accordingly, there exists in the art a need to overcome the existingdisadvantages of the prior proposals, and it is therefore a generalobject of the present invention to provide an improved valve whichavoids these disadvantages.

More particularly, it is an object of the present invention to providean improved valve of the type here generally under discussion, but whichhas a much more rapid response time than the prior-art valves.

Another object of the invention is to provide such an improved valvewhich, despite its improved characteristics, is relatively simple in itsconstruction and highly reliable in its operation.

In pursuance of the above objects, and of others which will becomeapparent hereafter, one feature of the invention resides in a valve, ina combination which briefly stated comprises a housing having an inletfor pressurized fluid. A valve seat is provided in this housing and hasa seating surface and a valve member is exposed to the incomingpressurized fluid and has a coopcrating surface juxtaposed and normallyin engagement with the seating surface, with at least one of thesesurfaces being provided with a shallow recess. A conduit communicateswith the inlet and with the recess for the purpose of admitting into thelatter sufficient pressurized fluid to lift the valve member off thevalve seat. A control valve is interposed in this conduit and isoperable for permitting the flow of pressurized fluid therethrough.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawing.

FIG. la is an axial section through an exemplary embodiment of theinvention; and

FIG. lb is a view similar to FIG. 1, showing a portion of the valvewhich is mirror symmetrical with reference to that shown in FIG. la butwith the valve in a different operating position from that of FIG. 1.

Before discussing the two Figures in detail it is pointed out that FlGS. la and lb together constitute an axial section through a completevalve embodying the invention. However, in each Figure the valve isillustrated in a different operational position for the sake ofexplanation.

With this in mind, and referring both to FIGS. la and lb, it will beseen that the novel valve is designated in toto with reference numeral10. The valve has a housing 12 comprising a tubular circumferential wall18 and two end walls 20 and 22 located at the opposite open ends of theend wall 18 and connected with one another by threaded bolts 24.

The housing 12 has an inlet 14 for pressurized fluid and an outlet 16for the fluid.

A valve seat 28 is provided on the inner side of the end wall 22, thatis the side facing the interior of the housing and cooperates with avalve member 26. The cooperating surface of the valve member 26, that isthe surface which is juxtaposed with the seating surface of the valveseat 28, is provided with two concentric sealing rings 30 and 32, whichare maintained in place in suitable manner, for instance by retainingrings and screws passing through the retaining rings into the valvemember 26. The sealing rings 34) and 32 themselves may be metallicrings, O-rings of elastomeric material or the like. in fact, it ispossible to provide the cooperating surface of the valve member 26, inaddition or in lieu of the sealing rings 30 and 32, with appropriatesealing edges or sealing surface portions which can sealingly cooperatewith the seating surface of the valve seat 28.

In any case, the seating surface of the valve seat 28 and/or thecooperating surface of the valve member 26 is provided as illustratedwith a shallow recess 34 which in the illustrated embodiment is annular.Of course, if both of these surfaces are provided with such a recess 34,then the two recesses would have to communicate with one another whenthe surfaces are in sealing engagement. It is emphasized that the depthof the recess 34 has been exaggerated in the drawing for purposes ofclarity; in actual fact the depth of the annular recess 34, as seen inaxial direction of the latter, may for instance be on the order of somehundredth of a millimeter or some tenth of a millimeter. The innerdiameter of the recess 34 is somewhat greater than the diameter of thesealing ring 32, and the outer diameter of the recess 34 is somewhatsmaller than the diameter of the sealing ring 30, as shown.

A conduit 36 communicates with the inlet 14 as well as with the valveseat 28, where it opens into the recess 34 intermediate the sealingrings 30 and 32. It will be appreciated that a single or two or more ofthese conduits 36 can be provided, as a particular application mayrequire. interposed in the conduit 36 is an auxiliary valve 38 which maybe solenoid-operated or which may be a multi-way valve, as will bediscussed later.

A tubular portion Ml is provided which is fast with the valve member 26,for instance by being welded to it as indicated by the illustratedwelded seam, and which extends axially from the valve member 26 in thedirection in which the same will move when it lifts off the valve seat28. In the region of the opposite end of the tubular member 40 there isprovided another valve member, designated with reference numeral 42 andserving as a closure valve. This closure valve 42 cooperates with avalve seat 44 provided on the inner side of the end wall 20. A sealingring 46 is provided on the valve seat 44 and is maintained in place insuitable manner, for instance again by means of a retaining ring andscrews. The valve member 42 may be secured to the tubular member 40 inthe manner in which the latter has the valve member 26 secured to it, orit may be of one piece with the tubular member 40, as is illustrated inthe drawing.

The juxtaposed surfaces of the valve seat 414 and of the valve member 42are again provided with a shallow annular recess 48; as in the case ofthe recess 34, the recess 48 may be provided in the seating surface ofthe valve seat 44, in the cooperating surface of the valve member 42, orin both of them. The diameter of the recess 48 is so selected that it iswithin the outer diameter of the sealing ring 46. A conduit 50communicates with the inlet 14 and with the valve seat 44, opening intothe recess 48. interposed in the conduit 50 is a control valve orauxiliary valve 50 which may be of the same type as the valve 38.

As the drawing shows, the valve member 26 is connected pressure tightly,but with freedom of elastic axial movement, with the wall 18 of thehousing, via an inner tubular spring bellows member 54, a rigid sleeve56 and a ring member 58. The valve member 42 is similarly connected withthe wall 18 in pressure-tight but axially elastically yieldable manner,via a concentric outer spring bellows member 60 and the aforementionedring member 58. it will be seen that with this construction an annularchamber or clearance 64 exists between the housing 12 on the one handand the ring member, the bellows member 60 and the valve member 42 onthe other hand. The chamber 64 is in communication with the outlet 16 bymeans of substantially radial channels 72 in the valve member 42 and anaxial channel 70 in the tubular member 40. An additional chamber 62 isdefined by the inner bellows member 54 and the sleeve 56, communicationwith the inlet 14. The operation of my novel valve will be readilyunderstood from what has been set forth above. Pressurized fluid isadmitted via the inlet 14 into an inlet chamber 15, exerting upon thevalve member 26 sufficient pressure to press it against the valve seat28 so that the valve prevents any passage of pressurized fluid from theinlet 14 to the outlet 16, because the sealing ring 30 seals the inletchamber with respect to the outlet 16.

if, now, the valve is to be opened and the passage of fluid from theinlet T4 to the outlet 16 is to be permitted, then the valve member 26must be lifted off its valve seat 28. For this purpose the control valve38 is operated so as to open communication between the inlet 14 and therecess 34 via the conduit 36. As mentioned before, the control valve 38may for instance be of the electromagnetically operated type, that is itmay be solenoid-operated.

As soon as the valve 38 is operated to permit flow of pressurized fluidfrom the inlet 14 through the conduit 36 into the recess 34, pressuredevelops in the recess 34 as a result of the incoming pressurized fluid.Because of the very small volume of the recess 34, the pressure thereinrises very rapidly to a sufiicient level, for instance withinapproximately 1 millisecond. This pressure now lifts the valve member 26off the valve seat 28, that is it moves the valve member 26 upwardly inH6. la so that it reaches the position illustrated in FIG. lb. A verysmall stroke, that is a very small movement of the valve member 26 outof engagement with the valve seat 28, is sufficient to permit the mainflow of pressurized fluid from the chamber 15 into the recess 34 and incontact with the cooperating working surface of the valve member 26,which latter is thereupon moved by the pressure of the main portion ofthe pressurized fluid to its fully open position in a very rapid time,for instance within approximately 2 milliseconds. To afford such accessof the fluid from the inlet chamber 15 to the working surface of thevalve member 26, it is merely necessary that the working surface moveaway from engagement with the valve seat 28 by a distance which may beas low as approximately 0.1 mm and which need not be more than severaltenths of a millimeter.

Of course, it will be appreciated that for proper operation of the valvein accordance with the concept of the invention, it is necessary thatthe surface area of the valve member 26 upon which the fluid admittedinto the recess 34 via the conduit 36 acts, is sufficiently greater thanthe surface area of the valve member 26 upon which the pressurized fluidin the inlet chamber 15 acts, so as to be able to counterbalance theaction of the pressurized fluid in the inlet chamber 15 and to overcomeit. it should be understood that no attempt has been made in FlGS. laand lb to show these relationships, inasmuch as this is well within theskill of the art.

While the valve member 26 is in closed position, and during the entiretime required for the valve member 26 to move to fully open position,the auxiliary or control valve 52 is in closed position. Similarly, whenthe valve member 26 has reached its fully open position, the valve 38 isalso closed again. it will be appreciated that when the valve member 26is in fully open position, the valve member 42 is in sealing engagementwith its valve seat 44 against which it is urged by the admittedpressurized fluid, as shown in FIG. lb.

in the position shown in HS. lb, that is when the valve is open, thechamber 64 communicates with the outlet 16 via the channels and 72, sothat the same pressure level obtains in the chamber 64 as in the outlet16.

if the valve is subsequently to be closed again, that is to be returnedfrom the position of FIG. llb to the position of FlG. la, then thecontrol valve 52 is opened. This valve may also be electromagneticallyoperated. When it is opened, it permits the flow of pressurized fluidfrom the inlet 14 via the conduit Eil into the recess 48. The sameresults are now obtained with respect to the valve member 42 which werepreviously obtained with respect to the valve member 26. In other words,pressure in the small-volume recess 48 builds up very rapidly until itis sufficient (again keeping in mind the necessary differential betweenthe surface areas of the valve member 42 which are impinged by the fluidin the recess 48 and by the fluid which acts upon the outer side of thevalve member 42) to lift the valve member 42 off the valve seat 44. Thismovement of course takes place in downward direction in FIGS. 1a and lbthereby shifting the tubular member 40 in the same direction and movingthe valve member 26 into sealing engagement with the valve seat 28. Thismovement permits the pressurized fluid from the chamber 64 to enter intothe recess 48 and now press against the working surface of the valvemember 42, and it is this main pressure which actually effects the majormovement of the valve member 42 and the valve member 26, the pressure inrecess 48 having been only sufficient to lift the valve member 42 farenough off the valve seat 44 to permit the entry of fluid from thechamber 64. This initial movement again can be very small, requiringonly a few tenths of a millimeter and it can be as small asapproximately O.1 mm so that the time required for a complete openingmovement of the valve member 42, and thus a complete closing movement ofthe valve member 26, is on the order to approximately 2 milliseconds.

During the closure movement, that is the movement of the valve member 26towards engagement with its valve seat 28, a closing pressure developsbetween the valve members 26 and 42 which is proportional to the surfacearea difference of the concentric tubular bellows members 54 and 60,because a force acts upon the valve member 26 in the direction of valveopening which equals the pressure of the pressurized fluid multiplied bythe surface area of the inner bellows member 54, whereas the valvemember 42 is under a force in the closing direction of the valve whichequals the pressure of the pressurized fluid multiplied by the surfacearea of the outer bellows member 60. The term surface area here isindicated to designate the cross-sectional area of the bellows members54 and 60, as designated by their diameters D, and D shown in thedrawing. Once the closure movement is completed, the control valve 52 isclosed again.

It is emphasized that a multi-way valve, for instance a three-way valve,can replace each of the valves 38 and 52, and that such a multi-wayvalve can in fact be used as a single valve controlling both of theconduits 36 and 50, rather than requiring two separate control vales 38and 52.

The drawing further illustrates the use of vent valves 66 and 68. Thesecan be but must not be provided. If they are provided, as shown, thenthey communicate with the recesses 34 and 48, respectively, theirpurpose being to vent the interior of these recesses to the exterior ofthe valve in the event that the sealing rings 40 or 46 should develop aleak because in this case the valve would switch unintentionally, thatis without being required to do so by operation of the valves 38 or 52,in the absence of such vent valves 66 and 68. If each of the valves 38and 52 is replaced by a three-way valve, as suggested above as apossibility, then the vent valves 66 and 68 can be omitted because theventing can then effected via the respective three-way valves.

It will be understood that each of the elements described agove, or twoor more together, may also find a useful application in other types ofconstructions differing from the types described above.

While the invention has been illustrated and described as embodied in avalve, it is-not intended to be limited to the details shown, sincevarious modifications and structural changes may be made withoutdeparting in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended 1. In a valve, a combination comprising ahousing having an inlet for pressurized fluid; a valve seat in saidhousing and having a seating surface; a valve member exposed to theincoming pressurized fluid and having a cooperating surface juxtaposedand normally in engagement with said seating surface, at least one ofsaid surfaces being provided with a shallow recess; a conduitcommunicating with said inlet and said recess for admitting into thelatter sufficient pressurized fluid to lift said valve member off saidvalve seat; and a control valve interposed in said conduit and operablefor permitting the flow of pressurized fluid therethrough.

2. A combination as defined in claim 1; further comprising an additionalvalve seat in said housing spaced from the first-mentioned valve seat indirection of movement of said valve member and having an additionalseating surface; an additional valve member connected for movement withthe first-mentioned valve member and having an additional cooperatingsurface, at least one of said additional surfaces having an additionalshallow recess; an additional conduit communicating with said inlet andwith said additional recess for admitting into the latter sufficientpressurized fluid to lift said additional valve member off saidadditional valve seat; and an additional control valve interposed insaid additional conduit and operable for permitting the flow ofpressurized fluid therethrough.

3. A combination as defined in claim 2; further comprising a firstspring bellows member connecting said first-mentioned valve member withsaid housing, and a second spring bellows member connecting saidadditional valve member with said housing.

4. A combination as defined in claim 3, said bellows members beingtubular and concentric with one another.

5. A combination as defined in claim 3, said bellows members beingtubular and said first member concentrically surrounding said secondbellows member and having an inner diameter greater than that of saidsecond bellows member.

6. A combination as defined in claim 2; and further comprising a pair ofventing valves each provided at one of said valve seats andcommunicating with the respective seating surface thereof.

7. A combination as defined in claim 2, wherein each of said controlvalves is a multi-way valve.

municating with said inlet and with said additional recess for admittinginto the latter sufficient pressurized fluid to lift said additionalvalve member off said additional valve seat; and wherein said controlvalve is a multi-way valve interposed in both of said conduits andoperable for selectively permitting the flow of pressurized fluidthrough a respective one of said conduits.

1. In a valve, a combination comprising a housing having an inlet forpressurized fluid; a valve seat in said housing and having a seatingsurface; a valve member exposed to the incoming pressurized fluid andhaving a cooperating surface juxtaposed and normally in engagement withsaid seating surface, at least one of said surfaces being provided witha shallow recess; a conduit communicating with said inlet and saidrecess for admitting into the latter sufficient pressurized fluid tolift said vAlve member off said valve seat; and a control valveinterposed in said conduit and operable for permitting the flow ofpressurized fluid therethrough.
 2. A combination as defined in claim 1;further comprising an additional valve seat in said housing spaced fromthe first-mentioned valve seat in direction of movement of said valvemember and having an additional seating surface; an additional valvemember connected for movement with the first-mentioned valve member andhaving an additional cooperating surface, at least one of saidadditional surfaces having an additional shallow recess; an additionalconduit communicating with said inlet and with said additional recessfor admitting into the latter sufficient pressurized fluid to lift saidadditional valve member off said additional valve seat; and anadditional control valve interposed in said additional conduit andoperable for permitting the flow of pressurized fluid therethrough.
 3. Acombination as defined in claim 2; further comprising a first springbellows member connecting said first-mentioned valve member with saidhousing, and a second spring bellows member connecting said additionalvalve member with said housing.
 4. A combination as defined in claim 3,said bellows members being tubular and concentric with one another.
 5. Acombination as defined in claim 3, said bellows members being tubularand said first member concentrically surrounding said second bellowsmember and having an inner diameter greater than that of said secondbellows member.
 6. A combination as defined in claim 2; and furthercomprising a pair of venting valves each provided at one of said valveseats and communicating with the respective seating surface thereof. 7.A combination as defined in claim 2, wherein each of said control valvesis a multi-way valve.
 8. A combination as defined in claim 1; furthercomprising an additional valve seat in said housing spaced from thefirst-mentioned valve seat in direction of movement of said valve memberand having an additional seating surface; an additional valve memberconnected for movement with the first-mentioned valve member and havingan additional cooperating surface, at least one of said additionalsurfaces having an additional shallow recess; and an additional conduitcommunicating with said inlet and with said additional recess foradmitting into the latter sufficient pressurized fluid to lift saidadditional valve member off said additional valve seat; and wherein saidcontrol valve is a multi-way valve interposed in both of said conduitsand operable for selectively permitting the flow of pressurized fluidthrough a respective one of said conduits.